Improvement in tebeading tubes



2 She ets-+Sheet i.

D. SAUNDERS.

, THREADING TUBES.

No. 76,823.v PatentedApr. 14:, 1868.

2 Sheets-Sheet 2.

D. SAUNDERS. THREADING TUBES.

I .9 u I e -mtrh tetra ntent ffxre.

DAVlD SAUNDERS, 10F nnooKnvnnssieson To JOSEPH NASON- 8100.,

OFNEW YORK CITY, N. Y

Letters 1mn 1vo. 76.e23, (dated, April 14, 1868.

IMPROVEMENT IN THREADING TUBES- ll1t'.tlgthnlt matrix in in tips: itettasgatent ant mating ntrtnf the 5mm.

TO ALL-WHOM IT MAY CONCERN: I 7

Be it known that L'DAVID SAUNDERS, of Brooklyn, in the county of Kings, and State of New York, have invented certain new and useful Improvements in Means for Producing the Screw-Threads Required on -the Ends of Gas-Pipes and analogous round objects; and I do hereby declare that the following is a full and exact description thereof. I

I willfirst describe what I consider the best means of carrying out my invention, and will afterwards designate the point. which I believe to be new. therein. The accompanying drawings form a part of this specification. v I i I l Figure 1 is. a face view with the lever G out ed at the line ab, to allow its being all shown on a small sheet of paper.

It should be understood thatthe part represented in Figure lisa continuation of tbe'lever G, represented in fig. 1. I v I Figure 2 is a side elevation, partly in section.

Figures 3 and4 are details, detached.

Similar letters of reference indicate like parts in all the figures;

A is the die, which may be producedin the usual or any approved form adapted to cut the-thread desired. It is locked in the pinion B by means of the hey a, and is covered and confined, when in use, by the plate B, which turns on the. pivot 15, and locks under the head of the screw ba G is the leader piecqwhieh is adapted to be confined in a fixed relation to the pipe to be treated, and is threaded on its extcrior,.as also the piece B on its interior, with a thread, which corresponds in pitch to that which'it is desired to produce 0n the gas'pipe. r other articleto be treated, indicatedjin these figures in red lines, and marked M.

So far as yet described, my apparatus is" of an ordinary and well-approved description. 'The novelty in my invention relates to the means of holding the leader-piece, and operating'the other piece, B, and its connecters relatively thereto.- My invention affords a more conv'en ienttmanner of operating than has heretofore. been known. It allowsthe pipe tobe threaded without the necessity for a vise, and with a greater purchase or leverage in the operating-device than has been heretofore practicable with devices operating in an analogous uianner.

The leadervpiece C is fixed directly on the material, M, which I will term the gas-pipe. It is secured firmly by means of the pinching-screws D 13*, and is provided with an arm, C, which is produced with a hole in the side, adapted to receive a bar, E, by which the entire apparatus may be conveniently steadied and supported by the hand. A lever, G,'is pivoted to;a boss,-C on the ox tremity of the arm C, by means of a stud,f, as represented. The device is operated by vibrating the lever G. A pawl, H, is connected to the levcr'G by the pin it, placed near the pivot or fulcrum of the lever G, and adapted, as represented, to catch in the teeth 'ofthe piece B, and to move it a little at each vibration. I is a spring, which keeps the pawl H constantly in position to be effective. i

By reason of the fact that my lover G turns on the pivotb, located outside of the piece B, insteadjof turning on a centre, which is in the line of the axis of the pipe which is being treated, I am'able to obtain a'gre'at leverage, and to work with great facility. The-force turning the part B around the gas-pipe, may, by my invention, be made fourfold, or any other desired proportion, greater than the force exerted on the lever G,and resisted by the lever E;- that is to say, assuming, as must almost necessarily be the case, that the angularstrain on the lever G and the handle or supporting-bar E is equal, the force tending to turn the piece B, and'conseqncntly torcut the desired thread on thc'gas-pipe, may be twice, or fourtimes, or any other proportion'greater,

' by making the distance between the pointsfand h proportionately short.

Having now fully described my invention, what I claim as new, and desire to secure by Letters Patent, is as follows: v p I p I claim the threading tocl herein described, constructed and arrangedsubstantially as'herein set forth.

' D. SAUNDERS.

Witnesses: Y W. C. Dav, O. G. Lzvmes. 

